Saw grinder



Nov. 18, 1930. E. P. ARMSTRONG SAW GRINDER Filed May 28, 1927 2 Sheets-Sheet 1 "m M W, a

11 Yet we NOV. 18, 1930. NG 1,781,941

SAW GRINDER Filed May 28, 192' 2 Sheets-Sheet 2 Patented Nov. 18, 1930 UNITED STATE j 7 EDWA-RD rmnms rno ve, orrorammnn. oime'olvf I sAw RIND'ER- Application-filed my 1927. -se riai m; 195,097.]:

My invention -relates*t saw grinders for circular saws of the type commonly used" as trimmer saws, and the like. P principalobje'ct of my invention isto provide an economical; circular saw grinder adapted for use in small saw mills, box factories, and the like, which maybe located near the saw, and which is simple in construction and operatiombut which will meet all the requirements for keeping thejsaws of this class sharp and properlyground' Another object of my invention is to pro 'vide a saw. grinder adapteam center the grinding'wheel on the saw,'1. e., to set the grinding wheel sothat itwill grind the tooth I I 4 4 of Fig. 1, and. illustrates certa'in de-' at the correct angle with the center of the saw; andwhich will maintainsuch position during the other angular adjustment of the {grinding wheel as well as when it is set to grind square;

' provide a 'sawigrinder adapted to be used Lon saws offrom seven to fifty-fouriinches in diameter which feature is important, as out ofi and-trimmer saws of difierent diameters are used in allplants of this character.

' i I attain these and other incidentalvobjects I in a" saw grinding device comprising a verwith anarcuate extensionpivotally fastened to a .post; in vertical alinementwith said socket and provided 'with means for locking said vertical member 'inangular horizontal relation with a grinding head, and said member adapted to have a saw clamped thereon. I

ments of of Fig. 3, and construction? I Fig.9 shows a section taken on the line 9 9 The grinding head vbeing normally held 1 out be operative engagement with the saw,

- and comprisinga frame carrying a'driven grinding wheel, adapted to bepiv'otally fixed to: said post for movement in a vertical planeswhereby the saw'clamped on Saidvertical' m'ember jmay be rotated about the axis of rotation'of said member, and at the same time maintained invertical alinement with thecentefriof said grindi'ngrwheel.

transversely and the grinding head normally raised out of operative engagement with the saw s K Fig-. 3 shows a view similar tofFig. 2 except the .saw is positioned for having the beveled edges of the teeth ground; l

Fig. 4 showsa section taken on'the line tails of construction; 1 Figs. 5 and J6 and 7* show the three adjustthe saw relatively tothe grinding wheel; f 1

Fig. 8 shows a section taken on the line 8-8 illustrates certain details "of of'Fig. 3, and "illustrates further details .of 7

construction. I a V a a inventionhcomprises a vertically arranged member a or post mounted in. an arm 6, the other end of the arm being pivotally mounted on a plate 0, fixed in the floor of the mill.

The upper end of the post a with an'arcuate extension d, which is pivotally fixed as at e in abracket g boltedto any convenient upright support f. of the mill. The extension 03 is so. formed and the bracket g'lis so arranged that the pivotediend is provided 60 The details oficonstruction and the mode of operation of. invention will herein after be described in detail with reference to the accompanyingdrawings, in which:

Fig. shows a 'pe'rspective, view. of my saw grinder-and illustrates the'details of 'construction;""- 1 Fig. 2 shows a perspective view" similarto r Y 1 ,"with a saw -mounted in place, and "illustrates the saw positionedto be ground e is in exact vertical alinement with the socket c.

The bracket 9 is provided with a circular segment 5 provided with notches 6, 7 and 8, and the upper end of the extension (Z is provided witha lug 9, provided witha set screw 10 adapted to be set in any one of the three notches so that the post a and the extension at may be locked in anyone of the three positions. r

A pendent arm '2', is pivoted to the extension a? and provided with an arcua'te'segment j adapted to slide in a bracket 7: fixed on the post a by a set screw 76 and a saw carrying, stud h, on which a clamping nut is threaded, is slidably mounted on the arm i.

.An outstandingguidebar Z is provided on the upper end of the arm 2', adjacentits pivoted end and serves as a guide against which the saw 3 will bear when the sawis clamped onthestudh, J p a .1

A grinder head is provided comprising a frame p pivotally fixed for vertical move ment to a bracket q, the bracket; qadapted to be fixed on thesame upright support f as the bracket g, but below it," so thata grinding wheel 1 mounted'on a shaft-s which is journaled on the'iramep and driven bya belt t mounted over pulleys ur and a), will coincide exactly with the vertical alinement ofthe two ends of the support a. r r

A downwardly extending rod n is fixedon the frame p which, whenthe grinder wheel is brought into operative engagement'with the saw, will serve as a stop by striking against a curved finger m provided on, the lower end of the extension d.

A coil spring y is fixed to the frame 37 and to any convenient point abovethe said frame, whereby thevgrinding wheel will normally be held out of operative engagement with the saw.

The frontportion of the frame 7 is rounded and forms an operatinghandle p by which the operator may move the grindingwheel into operative engagement with the saw,

7 against the action of the spring y.

The operation of my invention is as follows: r v I v The arbor h is adjusted correctly for the diameter ofthe saw to'be ground, by sliding it on the arm 2' until'the distance from the periphery of the grinding wheel when in operative engagement is equal to the radius of the saw to be ground and then clamping the bracketlc on the post a by the nut by this construction the teeth will always be ground at the proper angle with the center of the saw. 7 v

The saw 3 having been clamped on the arbor 'h, the post a will'be rotatedabout the grinder head, until the saw is brought into .such angular relation to the grinding wheel,

that aright beveled tooth, the square cuttingfacepor theleft beveled tooth, maybe notches in the circular segment 5 at such points as the additional adjustments are desired.

By constructing the post a so that it may be revolved'about a fixed point, and by ar- 77 ranging the grinder wheel so that it coincides with avertical axis through said fixed point,

when in operative engagement withthe tooth ofsaid saw, I provide a saw-grinding device by which the various angles at which the saw teeth are to beground maybe adjusted by merely rotating the posta on which the saw is clamped, about the grinding wheel and set for grinding a toothwhich is beveled on its right side, then may be transversely ground on itsface and finally'setting the vmember a. so the next tooth which is beveled on its left side may be ground, all of which is done efiiciently with one adjustmentof the saw on the arbor h, with considerable sav ingintime. I

Iclaim: v a 1'. In combination with a saw-tooth grind er, asaw-bladesupport comprising, a supporting arm pivotedat one end to the floor,

a post carried by the free end of saidarm, an offset extension on said post to a point above the grinding wheel of the grinder, said extension having .a lateral projection, a bracket to which the upper end of said extension is pivoted, the axes oft-he said two pivots coinciding, a pendent arm pivoted at its upper end to the said lateral projection, and means adjustable on said pendent arm for. clamping the saw-blade thereon.

2. In combination with a saw-toothgrind- .er, a saw-blade support, comprising, a supporting arm pivotedat one end to the-floor, a post carried by the free endfof said arm, an. offset .extension'on said post to a point above the grinding wheel of the grinder, said extension having a lateral projection, a bracket to which the upper end ofsa'id extension is pivoted, the axes of the said two -pivots'coinciding,fa pendent arm pivoted,

atits upper end to the said lateral projection, an arcuate guide memberwcarrie'd by the lower endof-said pendent arm, a guide element on said post with which said arcuate guide member cooperates, and means adjustable on said pendent arm for clamping the saw-blade thereon. A p t V I 3. In combination with a saw-toothgrinder, a saw-blade support, comprising, a supporting arm pivoted at one end to the floor and provided with a socket atits other end,

a post carried by the free end of said arm, anoffset extension onsaid post to a point above the grinding wheel of the grinder, said extension having a lateral projection, a bracket to which the upper end ofsaidextension is pivoted, the axes of the s aid two pivots coinciding, a pendent arm pivoted at its upper end to the said lateral projection, an arcuate guide member carriedi b .the lower end of said pendent arm, a gui e element on said post with which said arcuate guide member cooperates, means adjustable on said pendent arm for clamping the sawblade thereon, and a stop provided onthe upper end of said post for limiting the downward movement of said wards the saw-blade.

EDWARD P; ARMSTRONG.

grinder wheel to- 

